frozen

I bought a set of Ross Racing Pistons from Cypher, and they came with Ross Racing Rings.

Instructions here.
http://www.rosspistons.thinkhost.com/resou...NSTRUCTIONS.pdf

Now from reading it over, it looks pretty specific, requiring some professional machine shop installation. I was just planning on using a hone ball on the cylinders, putting the rings on and pop the pistons in. How crucial is it to maintain these exact numbers? It says these rings are oversized, so I'm thinking of just filing them down until they fit in the cylinders with a small gap, and then take it from there. I understand that rings are what seal the piston in the cylinder, however I doubt that most rings are installed to these very precise specifications.

Looking for opinions. I have very little background in machining (pretty much none). I have a digital caliper fing02.gif

tanc

Actually, yes most rings are installed like mentioned in the pdf. What don't you understand, the pdf is pretty straight forward. But you say the piston rings are oversized? Are the pistons oversized too? You need to list specs of what you have, piston wise and block wise.

Cypher

The pistons are a HAIR over stock like 82.06" to give room to hone out the cylinders for a nice cross hatch pattern to them. That is it.

Denisst99

what is the EXACT sizes of your new pistons and what are your 4 bopre size in yur engine block?

you don't want oval or tapered bores, and you need (with out seing the specs) 0.003" of clearance between the pistons and cylinder
i never really like stock bore pistons because unless you have a very low milage engine you always end up with some taper and not so round cylinder

for the ring you needa specific minimum gap usually about 0.004" to 0.005" for each inches of bore size

so if you have a bore of 4" you need usually 0.016" to 0.020" of ring gap

ring gaps should be filed square and deburred once proper clearnace is made

frozen

As Cypher said the pistons are 82.06mm. The first paragraph in the PDF says the rings are oversized. Alright, I didn't realize the rings were so specific. Thanks.

4g64fiero

http://www.muller.net/sonny/crx/rings/index.html

That should clear up some of your questions.

Denisst99

82.06mm means their oversized by 0.002"
not enough to clear up medium problem in the bore..
anyway,
first measure you bore in at least 4 places,measure the pistons with this reference then decided wich piston goes in wich hole,
you will need to at least rough up the bores a bit and might also need to do a quick re-hone job to the cylinder if the dimension ask for it

David Dickson

In addition to what Denis says you need to file the Gap for each ring in accordance to your desired boost level. Each ring will have a different gap to boost recommendation from ROSS. And YES you NEED to use the rings that came with your piston because OEM rings will expand at a different rate when compared to aftermarket rings. CP Pistons was VERY specific about what each ring cap should be for desired boost levels. Here's there ring gap calculator. Also I recommend picking up a ring gap tool if you are going to be doing it yourself as it will make sure the ring ends are filed exactly square.

CP Piston Ring Gap Specs

frozen

Just to update this, I eventually realized that I did not get Ross Racing Rings, they are actually TotalSeal top rings, and then regular 2nd rings. The top ring is actally two rings, with each gap 180 degrees apart. There is a tiny gap on the top ring once the 2nd top ring is installed, which creates pressure on the INSIDE of the ring, pushing it out towards the cylinder walls during combustion. Once I get my flex hone I'll be gapping these with a diy dremel ring gapper setup I found on another forum, along with a feeler gauge. It seems each tiny part of this build involves about 5 hours of research and reading, I never thought I would learn so much about engines.

Stocker

You don't have to learn so much. You only have to learn so much to do it right and know why it was right.